阅读说明：本技术 一种功率电感及其制备方法、系统级封装模组 (Power inductor and preparation method thereof, and system-in-package module ) 是由 胡小情 智彦军 景遐明 于 2020-08-09 设计创作，主要内容包括：本申请提供了一种功率电感及其制备方法、系统级封装模组,功率电感应用于系统级封装模组中。功率电感包括绕组,以及金属磁粉芯；其中,金属磁粉芯用于支撑绕组,绕组采用金属导片。在组装时,金属磁粉芯与绕组一体压制而成,金属磁粉芯包裹绕组,且金属磁粉芯与绕组之间绝缘；绕组具有第一端脚和第二端脚；第一端脚和第二端脚外露在金属磁粉芯不同的表面。通过在功率电感不同的两面分别设置端脚,使得功率电感可匹配到不同方向布置器件的系统级封装模组中,方便了电感的设置。另外,通过绕组采用金属导片并与金属磁粉芯一体压制而成,提高功率电感的电感量,降低电感的损耗,提高电感的小型化。(The application provides a power inductor, a preparation method thereof and a system-in-package module. The power inductor comprises a winding and a metal magnetic powder core; the metal magnetic powder core is used for supporting the winding, and the winding adopts a metal guide sheet. During assembly, the metal magnetic powder core and the winding are integrally pressed, the metal magnetic powder core wraps the winding, and the metal magnetic powder core and the winding are insulated; the winding is provided with a first terminal pin and a second terminal pin; the first terminal pin and the second terminal pin are exposed on different surfaces of the metal magnetic powder core. The terminal pins are respectively arranged on the two different sides of the power inductor, so that the power inductor can be matched with system-in-package modules with devices arranged in different directions, and the setting of the inductor is facilitated. In addition, the winding is formed by pressing the metal conducting sheet and the metal magnetic powder core integrally, so that the inductance of the power inductor is improved, the loss of the inductor is reduced, and the miniaturization of the inductor is improved.)

1. A power inductor, comprising: winding and metal magnetic powder core; wherein the content of the first and second substances,

the metal magnetic powder core wraps the winding, and the metal magnetic powder core is insulated from the winding;

the winding is a metal conducting sheet and is provided with a first terminal pin and a second terminal pin; the first end pin and the second end pin are exposed on different surfaces of the metal magnetic powder core.

2. The power inductor according to claim 1, wherein the winding comprises a main structure, and a first connection structure and a second connection structure connected with two ends of the main structure in a one-to-one correspondence manner; wherein the content of the first and second substances,

the first connecting structure comprises the first end pin;

the second connection structure includes the second terminal pin.

3. The power inductor of claim 2, wherein the second connection structure further comprises a third terminal pin;

the third terminal pin and the first terminal pin are positioned on the same surface.

4. A power inductor according to claim 3, wherein the first current path length is less than the second current path length; wherein the content of the first and second substances,

the first current path length is a current path length from the first terminal pin to the second terminal pin;

the second current path length is a current path length from the third terminal pin to the second terminal pin.

5. The power inductor of any one of claims 2 to 4, wherein the body structure is Z-shaped, wherein,

the first connecting structure is connected with one end part of the Z-shaped main body structure;

the second connecting structure is connected to the other end of the Z-shaped body structure.

6. The power inductor according to any one of claims 1-5, wherein the winding is a stamped and formed bare copper sheet.

7. The power inductor according to any one of claims 1 to 6, wherein the number of the windings is plural, and the plural windings are arranged in a single row.

8. A preparation method of a power inductor is characterized by comprising the following steps:

pressing metal magnetic powder cores in sections;

filling a winding into the metal magnetic powder core in the process of pressing the metal magnetic powder core in sections; wherein the content of the first and second substances,

the winding is a metal conducting sheet and is provided with a first terminal pin and a second terminal pin; the first end pin and the second end pin are exposed on different surfaces of the metal magnetic powder core.

9. The method of claim 8, further comprising: after the metal magnetic powder core is pressed in sections, high-temperature annealing is carried out.

10. The method of claim 9, wherein the high temperature anneal has an anneal temperature of not less than 400 ℃.

11. The method according to any one of claims 8 to 10, wherein the step-pressing of the metal magnetic powder core specifically comprises:

pressing the metal magnetic powder core in two sections; or the like, or, alternatively,

and pressing the metal magnetic powder core in three sections.

12. A system-in-package module, comprising a circuit board, and the power inductor according to any one of claims 1-7 disposed on the circuit board.

Technical Field

The present application relates to the field of electronic technologies, and in particular, to a power inductor, a manufacturing method thereof, and a system-in-package module.

Background

The rapid development of electronic products requires that IC devices continuously evolve toward a direction of stronger functions and higher integration, however, as the moore's law of the IC industry gradually approaches the physical limit, further integration of chip processes is greatly challenged, and thus a System In Package (SiP) module for integrally packaging various devices is developed. However, the existing SiP module generally performs plastic package on the whole after the devices are tiled and interconnected, so that the space size in the plane direction is difficult to reduce; meanwhile, the heat dissipation of the back of the device is greatly limited by the guiding out of the plastic package material, and the circuit connection is only guided out from the bottom of a single surface, so that a great deal of limitation is formed on the high-efficiency integration and heat dissipation of the product. Therefore, by increasing the integration of devices in the vertical direction, a Power System In Package (PSiP) module achieves high Power and miniaturization. However, the arrangement mode of pin pins on the same plane of the device in the prior art cannot be matched with the existing highly integrated PSiP module of the device in the vertical direction.

Disclosure of Invention

The application provides a power inductor, a preparation method thereof and a system-in-package module, which are used for improving the adaptability of the inductor and reducing the loss of the inductor.

The application provides a power inductor, which is applied to a system-in-package module. The power inductor comprises a winding and a metal magnetic powder core; the metal magnetic powder core is used for supporting the winding, and the winding adopts a metal guide sheet. During assembly, the metal magnetic powder core and the winding are integrally pressed, the metal magnetic powder core wraps the winding, and the metal magnetic powder core and the winding are insulated; the winding has a first terminal pin and a second terminal pin; the first end pin and the second end pin are exposed on different surfaces of the metal magnetic powder core. The terminal pins are respectively arranged on the two different sides of the power inductor, so that the power inductor can be matched with system-in-package modules with devices arranged in different directions, and the setting of the inductor is facilitated. In addition, the winding is formed by pressing the metal conducting sheet and the metal magnetic powder core integrally, so that the inductance of the power inductor is improved, the loss of the inductor is reduced, and the miniaturization of the inductor is improved.

In a specific embodiment, the metal magnetic powder core is provided with a first outer surface and a second outer surface which are opposite, the first end pin is exposed on the first outer surface, and the second end pin is exposed on the second outer surface. The adaptability of the power inductor is improved.

In a specific embodiment, the winding includes a main structure, and a first connection structure and a second connection structure connected to two ends of the main structure in a one-to-one correspondence manner; wherein the first connecting structure comprises the first terminal pin; the second connection structure includes the second terminal pin. The power inductor is connected with the main body structure through the two connecting structures and serves as a terminal pin of the power inductor.

In a specific embodiment, the first connecting structure, the second connecting structure and the main body structure are a unitary structure. The resistance of the winding is reduced.

In a specific embodiment, the second connecting structure further comprises a third terminal pin; the third terminal pin and the first terminal pin are positioned on the same surface. The plurality of terminal pins are formed so that the inductors have different current paths.

In a specific embodiment, the first current path length is less than the second current path length; wherein the first current path length is a current path length from a first terminal pin to the second terminal pin; the second current path length is a current path length from the third terminal pin to the second terminal pin. And different connection scenes are adapted.

In a particular embodiment, the body structure is Z-shaped, wherein the first connecting structure is connected to one end of the Z-shaped body structure; the second connecting structure is connected to the other end of the Z-shaped body structure. The space volume occupied by the inductor is reduced.

In a specific possible embodiment, the main body structure can also be L-shaped, S-shaped, M-shaped and the like. Different inductance values may be provided.

In a specific embodiment, the winding is a stamped and formed bare copper sheet. The resistance of the power inductor is reduced, and the loss of the power inductor is reduced.

In a specific possible embodiment, the number of the windings is plural, and the plural windings are arranged in a single row. The modularization is convenient.

In a second aspect, a method for manufacturing a power inductor is provided, where the method includes the following steps:

pressing metal magnetic powder cores in sections;

filling a winding into the metal magnetic powder core in the process of pressing the metal magnetic powder core in sections; wherein the content of the first and second substances,

the winding is a metal conducting sheet and is provided with a first terminal pin and a second terminal pin; the first end pin and the second end pin are exposed on different surfaces of the metal magnetic powder core.

In the technical scheme, the magnetic cores are partially pressed in a segmented mode, pressure in the inductor forming process is increased, the magnetic conductivity of the metal magnetic powder core material can be improved, the inductance value is improved, and therefore inductor miniaturization is facilitated. Meanwhile, the two different surfaces of the power inductor are respectively provided with the terminal pins, so that the power inductor can be matched with system-in-package modules of devices arranged in different directions.

In a specific possible embodiment, the method further comprises: and after the metal magnetic powder core is pressed in sections, high-temperature annealing is carried out. And high-temperature annealing at the later stage of pressing is carried out, so that the loss of the magnetic material is greatly reduced, the overall loss of the inductor is finally reduced, and the inductor is ensured to have lower working temperature.

In a specific embodiment, the annealing temperature of the high temperature annealing is not lower than 400 ℃. The loss of the magnetic material is reduced, and the overall loss of the inductor is finally reduced, so that the inductor is ensured to have lower working temperature.

In a specific embodiment, the annealing temperature may be 500 ℃, 600 ℃, 700 ℃, and the like. When high-temperature annealing is adopted, the loss of the magnetic material is reduced, and finally the integral loss of the inductor is reduced.

In a specific possible embodiment, the step-pressing the metal magnetic powder core specifically includes: pressing the metal magnetic powder core in two sections; or, the metal magnetic powder core is pressed in three sections. The sectional pressing may be performed in different ways depending on the shape of the winding.

In a third aspect, a system in package module is provided, which includes a circuit board, and the power inductor disposed on the circuit board. The two opposite sides of the power inductor are respectively provided with the terminal pins, so that the power inductor can be matched with a system-in-package module with devices arranged in the vertical direction, and the arrangement of the inductor is facilitated.

Drawings

Fig. 1 is a schematic view of an application scenario of a power inductor in the prior art;

fig. 2 is a perspective view of a power inductor provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of a winding of a power inductor according to an embodiment of the present application;

FIG. 4 is a top view of a winding provided by an embodiment of the present application;

fig. 5 is a schematic diagram of a current flowing in a winding when a terminal pin of a power inductor according to an embodiment of the present application is connected;

fig. 6 is a schematic diagram of a current flowing in a winding when another terminal pin of the power inductor provided in the embodiment of the present application is connected;

fig. 7 is a schematic diagram of a current flowing in a winding when the terminal pins of the power inductor according to the embodiment of the present application are connected;

fig. 8 is a schematic structural diagram of another power inductor provided in the embodiment of the present application;

fig. 9 to 12 are schematic diagrams illustrating a process for manufacturing a power inductor according to an embodiment of the present disclosure.

Detailed Description

The embodiments of the present application will be further described with reference to the accompanying drawings.

First, an application scenario of the inductor provided in the embodiment of the present application is described, where the inductor may be applied to various electronic devices, for example, the inductor may be used as a core device of a power DC/DC converter, and is widely applied to the fields of industrial equipment, consumer electronics, chip power supply, and the like, and is particularly applied to a buck converter packaging module for supplying power to high-power consumer electronics and a large-current chip. For a high-frequency large-current DC/DC power conversion system-in-package module, since high integration is required, an inductor needs to have small volume, low loss and high DC bias characteristics, and simultaneously, the requirement of device integration in the vertical direction needs to be met. As shown in fig. 1, the system-in-package module includes a substrate 1, a chip 2 disposed on one surface of the substrate 1, and an inductor 3 disposed on the opposite surface of the substrate 1. Chip 2 and inductance 3 all are connected with the circuit layer electricity of base plate 1, and chip 2 and inductance 3 all pass through the packaging layer encapsulation. Continuing to refer to fig. 1, since the inductor 3 has the PIN 4 on one side, and the PIN 4 is disposed on the side of the inductor 3 away from the substrate 1, when the inductor 3 is electrically connected to the substrate 1, the PIN 4 needs to be connected to the substrate 1 of the substrate 1 by forming the metal via hole 5 on the package layer. The electrical connection between the inductor 3 and the substrate 1 is troublesome, and therefore, the embodiment of the present application provides a power inductor. The power inductor provided by the embodiments of the present application is described in detail below with reference to the drawings and the embodiments.

Fig. 2 shows a schematic perspective view of a power inductor provided in an embodiment of the present application. The dashed line in fig. 2 represents the outline of the shielded portion of the structure in the power inductor and the internal outline of the power inductor.

The power inductor may include a winding 100 and a metal magnetic powder core 200. The metal magnetic powder core 200 is a main body structure of the power inductor, the shape of the metal magnetic powder core 200 is the shape of the power inductor, the winding 100 is located in the metal magnetic powder core 200, for example, the winding 100 may be located at the center of the power inductor, and the metal magnetic powder core 200 is pressed and molded on the periphery of the winding 100 and wraps the winding 100.

The metal magnetic powder core 200 is insulated from the winding 100 when prepared. When the metal magnetic powder core 200 is manufactured, the metal magnetic powder core is formed by pressing metal magnetic powder, and the outer surface of the metal magnetic powder is wrapped with an insulating organic material or an insulating inorganic material, so that the surface of the metal magnetic powder core 200 formed by pressing the metal magnetic powder has an insulating layer. When the metal magnetic powder core 200 wraps the winding 100, the insulating layer contacts the winding 100, and insulation is formed between the metal magnetic powder core 200 and the winding 100.

The winding 100 has a first terminal pin 121 and a second terminal pin 131, and the first terminal pin 121 and the second terminal pin 131 are exposed on different surfaces of the metal magnetic powder core 200. Different surfaces on the metal magnetic powder core 200 refer to different outer surfaces of the metal magnetic powder core 200, such as two adjacent outer surfaces, or two outer surfaces that are opposite to each other. Illustratively, the first terminal pin 121 and the second terminal pin 131 of the winding 100 are exposed on two outer surfaces of the metal magnetic powder core 200 opposite to each other, and the two outer surfaces are respectively used as surfaces for matching the power inductor with other components. Taking the metal magnetic powder core 200 as an example, the first outer surface 202 and the second outer surface 201 are surfaces when the power inductor is matched with other components, respectively. In connection with the application scenario shown in fig. 1, the first outer surface 202 may be a surface for mating with a substrate, and the second outer surface 201 is a surface opposite to the first outer surface 202. When assembled, the first terminal pin 121 of the winding 100 is exposed at the first outer surface 202; second terminal pin 131 is exposed at second outer surface 201. In use, the first terminal pin 121 and the second terminal pin 131 serve as external terminal pins of the power inductor, and current can flow in from the first terminal pin 121 or the second terminal pin 131 and flow out from the other terminal pin in the winding 100.

As an alternative, the winding 100 may also have three terminal pins, namely a first terminal pin 121, a second terminal pin 131 and a third terminal pin 132. Wherein the first terminal pin 121 and the third terminal pin 132 of the winding 100 are located on the same surface (the first outer surface 202) of the metal magnetic powder core 200. In use, the first terminal pin 121, the second terminal pin 131 and the third terminal pin 132 serve as external terminal pins of the power inductor, and current can flow in from one terminal pin among the first terminal pin 121, the second terminal pin 131 and the third terminal pin 132 and flow out from the other terminal pin among the three terminal pins.

When the winding 100 is coated with the metal magnetic powder core 200 in an insulating manner, the metal magnetic powder core 200 is coated around the winding 100 through a pressing process. In the pressing process, the pressure in the inductor forming process can be increased, the magnetic conductivity of the metal magnetic powder core 200 can be improved, the inductance value of the prepared power inductor is improved, and the miniaturization of the power inductor is facilitated. In addition, after the pressing is finished, the metal magnetic powder core 200 is annealed at a high temperature, so that the loss of the magnetic material can be greatly reduced, the working temperature of the power inductor is reduced, and the power inductor can be arranged at a position far away from a heat dispersion device in a system-level packaging module.

As an alternative, the metal magnetic powder core 200 is of a rectangular parallelepiped structure, but it should be understood that fig. 2 is only a specific example of the magnetic core powder core, the metal magnetic powder core 200 provided in the embodiment of the present application may be pressed into different shapes such as a cylinder, an elliptic cylinder, a cube, a trapezoid, and the like according to needs, and the specific shape only needs to be adapted to the assembly space of the power inductor.

The metal magnetic powder core 200 is a magnetic core made of metal alloy powder resistant to loss under high frequency conditions, and air gaps uniformly distributed in the metal magnetic powder core 200 do not leak magnetic flux and are not easily saturated under high direct current. Therefore, the power inductor prepared by the metal magnetic powder core 200 has the characteristics of high current, high frequency, miniaturization and the like.

The metal magnetic powder core 200 can be made of different types of materials, such as iron powder core, sendust core, high magnetic flux powder core, molypermalloy powder core, and the like. Wherein the iron powder core is formed by combining superfine iron powder and organic materials. The magnetic permeability of the iron powder core is between 10 and 75. The alloy components of the iron-silicon-aluminum magnetic core are 85% of iron, 9% of silicon and 6% of aluminum. The iron-silicon-aluminum magnetic core has low loss and hard material; the permeability of the sendust core may be 26, 60, 75, 90, 125, etc. The high magnetic flux powder core is an iron-nickel magnetic powder core, and the alloy powder of the high magnetic flux powder core can be composed of 50% of nickel and 50% of iron; the high-magnetic-flux powder core has the highest magnetic flux density, and the magnetic core loss is higher than that of Fe-Si-Al and lower than that of the Fe-powder core; the magnetic conductivity of the high-magnetic-flux powder core is within a range of 14-200. The composition of the molybdenum permalloy magnetic powder core is 2% of molybdenum, 81% of nickel and 17% of iron. Among the above magnetic powder cores, the molybdenum permalloy magnetic powder core has the lowest loss and the lowest saturation magnetic flux density. In addition, the temperature stability of the molybdenum permalloy magnetic powder core is good, and the magnetic conductivity is within the range of 14-550. As an optional scheme, the metal magnetic powder of the metal magnetic powder core 200 provided in this application embodiment may be prepared by using a material including ferrosilicon, ferrosilicon aluminum, ferrosilicon chromium, ferrosilicon aluminum nickel, and the like, and an insulating layer is wrapped on an outer surface layer of the metal magnetic powder, and specifically, the metal magnetic powder may be prepared by using an organic material or an inorganic material. For example, the organic material may be a resin such as epoxy resin, and the inorganic material may be a resin such as silicone resin.

Fig. 3 shows a schematic structural diagram of a winding provided in an embodiment of the present application. The winding 100 is a metal conductive sheet made of conductive metal material, such as copper, aluminum, and other metal materials with good conductive performance. For example, the winding 100 is made of a press-formed bare copper sheet, which has a good conductive performance and a low resistance, and reduces the heat generation amount of the power inductor, and has a low heat dissipation effect, unlike the case of making the winding with an enameled wire, so that the bare copper sheet can be assembled at a position far away from the heat dissipation device in the system-in-package module.

The winding 100 includes a body structure 110 and a connection structure. The connection structure provided by the embodiment of the present application includes a first connection structure 120 and a second connection structure 130. The first connection structures 120 and the second connection structures 130 are respectively arranged at two ends of the main body structure 110, and the first connection structures 120 and the second connection structures 130 are connected with two ends of the main body structure 110 in a one-to-one correspondence manner. It should be understood that the connections provided in the embodiments of the present application may include different connection manners such as soldering, electrical connection, or integral molding. As an alternative, the first connecting structure 120, the second connecting structure 130 and the main body structure 110 are manufactured by an integral molding process. For example, the winding 100 may be formed by stamping a copper sheet, or may be formed by processing after stamping, and the first connection structure 120, the second connection structure 130 and the main body structure 110 are an integral structure.

The first connection structure 120 extends to the first outer surface of the metal magnetic powder core, and the end of the first connection structure 120 extending to the first outer surface is used as a first terminal pin 121. The second connection structure 130 is extended to the second outer surface of the metal magnetic powder core, and the second connection structure 130 is extended to the end of the second outer surface as a second terminal pin 131. The first terminal pin 121 and the second terminal pin 131 are terminal pins for connecting the power inductor to a mating device. The first terminal pin 121 and the second terminal pin 131 are located on two opposite surfaces of the power inductor, so that the vertical power supply requirement can be met, and the power supply path is reduced. Therefore, the power inductor can be applied to a system-in-package module with vertical layout, and the adaptability of the power inductor is improved.

As an alternative, the first connecting structure 120, the second connecting structure 130 and the main body structure 110 are plate-shaped structures. In preparation, the first connecting structure 120, the second connecting structure 130 and the main body structure 110 may be formed by pressing, or integrally formed by casting.

Referring also to fig. 4, fig. 4 shows a top view of the winding. The main body structure 110 is Z-shaped, and the first connecting structure 120 is connected with one end of the Z-shaped main body structure 110; the second connecting structure 130 is connected to the other end of the Z-shaped body structure 110. When the structure is adopted, the main body structure 110 is bent to form a Z shape, so that the space volume occupied by the main body structure 110 can be reduced, and a longer winding 100 can be accommodated in the metal magnetic powder core. In combination with the perspective view of the power inductor shown in fig. 2, when the main body structure 110 is bent to form a Z shape, the power inductor can have a smaller volume under the same inductance. In addition, the main body structure adopts a Z-shaped structure, so that the magnetic density of the power inductor is more uniform, and the inductance is larger.

It should be understood that the winding shown in fig. 3 and 4 is only one specific example of the winding provided in the embodiments of the present application, and the winding provided in the embodiments of the present application may also take other shapes, for example, the main structure of the winding may also take other shapes such as an L shape, an S shape, an M shape, and the like.

As an alternative, the length directions of the first and second connection structures 120 and 130 are perpendicular to the length direction of the main body structure 110. When the winding 100 is wrapped by the metal magnetic powder core, the length directions of the first and second connection structures 120 and 130 are perpendicular to the first and second outer surfaces, and the length direction of the main body structure 110 is parallel to the first and second outer surfaces. When the metal magnetic powder core is pressed, the length direction of the main body structure 110 is parallel to the first outer surface and the second outer surface, so that the winding 100 is conveniently placed, and the production efficiency is improved.

It should be understood that the above-mentioned arrangement manner of the winding 100 is only a specific example provided in the embodiment of the present application, and in the winding 100 provided in the embodiment of the present application, a manner that an included angle between the length direction of the main body structure 110 and the length directions of the first connection structure 120 and the second connection structure 130 is an acute angle may also be adopted, but in any form, only the winding 100 may be wrapped by the metal magnetic powder core, and may be applied in the embodiment of the present application.

With continued reference to fig. 3, as an alternative, the second connecting structure 130 further extends to the first outer surface of the metal magnetic powder core, and the end of the second connecting structure 130 extending to the first outer surface is used as a third terminal 132. The first terminal 121 and the third terminal 132 are located on the same side and are arranged at intervals. The second terminal pin 131 is located on the opposite side, and three terminal pins can be used as connection terminals of the winding 100. In combination with the three-dimensional structure of the power inductor shown in fig. 2. The third terminal pin 132 formed by the second connection structure 130 increases the connection terminal pin of the power inductor and the matched device, and the first terminal pin 121 and the third terminal pin 132 are arranged at the first outer surface at intervals and both can be connected with the terminal pin matched with the power inductor. When the power inductor selects different terminal pins to be connected with a matched device, the power inductor with different inductance values can be formed.

The different current paths in the power inductor are explained below with reference to the drawings. For convenience of description of the current path, the flowing direction of the current is illustrated by a straight line with an arrow, but the current may also flow in the opposite direction indicated by the arrow in the current path.

Fig. 5 shows a schematic diagram of the current in the winding when one of the terminals of the power inductor is connected. When the first terminal 121 and the second terminal 131 of the power inductor are connected to the respective devices, the current flows from the first terminal 121 of the first connection structure 120, flows through the first connection structure 120, the main body structure 110, and a portion of the second connection structure 130, and then flows out from the second terminal 131. For convenience of description, the path length through which the current flows is referred to as a second current path length.

Fig. 6 shows a schematic diagram of the current in the winding when the other terminal pin of the power inductor is connected. When the third pin 132 and the second pin 131 of the power inductor are connected to the respective mating devices, current flows in from the third pin 132 of the second connection structure 130, and flows out from the second pin 131 only after flowing through the second connection structure 130.

As can be seen by comparing fig. 5 and 6, the first current path length is less than the second current path length. Therefore, the power inductor provided by the embodiment of the application can provide different inductance values when different terminal pins are selected to be matched with other devices.

Fig. 7 shows a schematic diagram of the current in the winding when the other terminal pins of the power inductor are connected. When the first terminal 121 and the third terminal 132 of the power inductor are connected to the respective devices, the current flows from the first terminal 121 of the first connection structure 120, and flows through the first connection structure 120, the main body structure 110, and a portion of the second connection structure 130, and then flows out from the third terminal 132 of the second connection structure 130. As can be seen from fig. 7, the power inductor provided in the embodiment of the present application can also be connected to a mating device through a terminal pin on the same surface.

As can be seen from fig. 5, 6 and 7, when the first terminal 121, the third terminal 132 and the second terminal 131 are used in the power inductor, the power inductor is applicable to different working scenarios, that is, applicable to a scenario in which the terminals on the two end surfaces are connected to different devices respectively, and also applicable to a scenario in which the power inductor is connected to the devices only through the terminals on the same surface. The applicability of the power inductor is greatly improved.

It should be understood that the number of the first terminal pins of the first outer surface provided in the embodiments of the present application may be different numbers, such as one, two, three, and the like, and similarly, the number of the second terminal pins of the second outer surface may also be different numbers, such as one, two, three, and the like. When the number of the first terminal pins and the second terminal pins is specifically set, the number can be determined according to the requirement of the power inductor.

Fig. 8 shows a schematic structural diagram of another power inductor provided in an embodiment of the present application. Reference may be made to fig. 2 for some of the reference numerals in fig. 8. The power inductor shown in fig. 8 is an integrated power inductor group, the power inductor group includes a plurality of windings 100, and two windings 100 are illustrated in fig. 8, but it should be understood that the power inductor 100 provided in the embodiments of the present application may include two, three, four, five, etc. different numbers of windings 100.

When the windings 100 are arranged, they may be arranged according to the application scenario. For example, the plurality of windings 100 may be arranged in an array, a single row, a triangle, or other different arrangements.

As an alternative, the plurality of windings 100 share the metal magnetic powder core 200, that is, when the metal magnetic powder core 200 is pressed, the plurality of windings 100 can be simultaneously insulated and coated, which facilitates modularization of the power inductor. Meanwhile, the integration of the two-phase or multi-phase power inductor is beneficial to reducing the volume of the device and meeting the requirement of a high-integration system-level packaging module in the vertical direction.

In order to facilitate understanding of the structure of the power inductor provided in the embodiments of the present application, a method for manufacturing the power inductor is described in detail below with reference to the accompanying drawings.

The preparation method comprises the following steps:

step 001: and pressing the first section of metal magnetic powder core.

As shown in fig. 9, a mold 300 is prepared, and the mold 300 is used to compress the power inductor. As shown in fig. 10, the metallic magnetic powder core is divided into a plurality of stages of pressing, and first, a first stage metallic magnetic powder core 210 to be pressed is put into a mold 300. Wherein, the metal magnetic powder core can adopt materials including iron silicon, iron silicon aluminum, iron silicon chromium, iron silicon aluminum nickel and the like.

Step 002: in the process of pressing the metal magnetic powder core in sections, filling the winding into the metal magnetic powder core;

as shown in fig. 11, the winding 100 is placed in a mold 300, and when the winding 100 is placed, it is ensured that the winding 100 is partially exposed on the first outer surface of the metal magnetic powder core and serves as a first terminal pin; and part of the second end pin is exposed on the second outer surface of the metal magnetic powder core and is used as a second end pin. The winding 100 is made of a bare copper sheet, which may be formed by punching a copper sheet or by processing after punching, unlike the winding made of an enameled wire. In addition, in addition to the first terminal pin and the second terminal pin shown in fig. 11 being located on the first outer surface and the second outer surface, respectively, the first terminal pin and the second terminal pin may also be located on different surfaces of the metal magnetic powder core, such as two adjacent surfaces.

Step 003: pressing the residual metal magnetic powder core;

specifically, as shown in fig. 12, the metal magnetic powder is put into a mold 300, the winding 100 is wrapped by the metal magnetic powder, the second stage of metal magnetic powder core 220 is pressed, and the winding 100 is insulated and wrapped in the metal magnetic powder core 200.

Step 004: after the metal magnetic powder core is pressed in sections, high-temperature annealing is carried out.

Specifically, high-temperature annealing at the later stage of pressing is carried out to form the power inductor. In the high temperature annealing, the annealing temperature of the high temperature annealing is not lower than 400 ℃, and exemplary annealing temperatures may be different temperatures such as 500 ℃, 600 ℃, 700 ℃ and the like. When high-temperature annealing is adopted, the loss of the magnetic material is reduced, and finally the integral loss of the inductor is reduced, so that the inductor is ensured to have lower working temperature.

As can be seen from the above description, in the power inductance press molding process, the metal magnetic powder core is pressed in sections according to the winding shape. For example, the metal magnetic powder core can be pressed by two sections, or the metal magnetic powder core can be pressed by three sections. For example, when two-stage pressing is adopted for the metal magnetic powder core, the lower half part of the water inlet magnetic powder core can be pressed first, and the upper half part of the metal magnetic powder core can be pressed. When three sections of pressing metal magnetic powder cores are adopted, the metal magnetic powder core magnetic cores at the upper part and the lower part can be pressed firstly, and the metal magnetic powder core at the middle part can be pressed again.

In addition, when the sectional pressing process is adopted, the pressure in the power inductor forming process can be increased, the magnetic conductivity of the metal magnetic powder core material can be improved, and the inductance of the metal magnetic powder core material can be improved, so that the miniaturization of the power inductor is facilitated under the condition of the same inductance.

The present disclosure also provides a system-in-package module, which refers to a packaging method in which all or most of the electronic functions of a system or subsystem are configured in an integrated substrate, and a chip is bonded to the integrated substrate. The system-in-package module not only can assemble a plurality of chips, but also can be used as a special processor, a dynamic random access memory, a flash memory and a passive element to combine a resistor, a capacitor, a connector, an antenna and the like, and all the modules are arranged on the same substrate. The system-in-package module provided by the embodiment of the application comprises a circuit board and any one of the power inductors arranged on the circuit board. The two opposite sides of the power inductor are respectively provided with the terminal pins, so that the power inductor can be matched with a system-in-package module with devices arranged in the vertical direction, and the power inductor is convenient to set. In addition, by adopting the power inductor, the system-in-package module can be formed in the vertical direction to increase the integration level of devices, and the high power and miniaturization of the system-in-package module are realized.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.